Inclinable headrest

ABSTRACT

A headrest inclinable relative to headrest stay(s), which is formed by a foaming process. The headiest has elongated hole(s) formed in the bottom thereof, with the headrest stay(s) extending outwardly through the elongated hole(s). Defined within the elongated hole(s) is an injected point where a liquid foaming agent has been injected into a headrest trim cover assembly during foaming process. Thus, in a resulting headrest formed thereby, such injected point is not viewed from a bottom of the headrest, when the headrest is inclined relative to the headrest stay(s), thereby maintaining an aesthetic appearance of the headrest.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a headrest which can be mounted via a headrest stay(s) on an automotive seat and is inclinable forwardly and backwardly relative to the headrest stay(s). Hereinafter, this headrest shall be referred to as “inclinable headrest” for simplicity. In particular, the invention is directed to an inclinable headrest of this kind which is formed by a foaming process wherein a liquid foaming agent is injected into an inside of a trim cover assembly preformed to have a predetermined contour of headrest, and then, the liquid foaming agent is cured to form an increased mass of foam padding filled in that trim cover assembly.

2. Description of Prior Art

In most cases, a headrest for use on automotive seat is formed through a foaming process which basically consists of the steps of performing a three-dimensional trim cover assembly in a predetermined shape of headrest by sewing together a plurality of cover materials, then placing a performed headrest frame in that trim cover assembly, together with headrest stays, thereafter, injecting a liquid foaming agent into the inside of the trim cover assembly, and subjecting all those elements to a foaming process by use of a foaming die apparatus. By such foaming process, all the trim cover assembly, headrest frame and headrest stays are formed together integrally into a resulting headrest wherein the liquid foaming agent has been cured into an increased mass of foam padding filled in the trim cover assembly. In this formation of headrest, it has been a common practice to preform an injection hole in a bottom side of the trim cover assembly prior to the foaming process, and in actual foaming operation, a liquid foaming agent is injected through such injection hole into the inside of the trim cover assembly, as known for example from the Japanese Laid-Open Patent Publication No. 9-11252.

Among various kinds of headrests formed in the foregoing foaming process, there has been known an inclinable headrest which allows a headrest body to be inclinable in forward and backward directions relative to a pair of headrest stays for example, wherein such pair of headrest stays are fixedly mounted on a seat back of automotive seat, so that a user can adjust forward and backward inclination of the headrest body to attain his or her preferred head support position. In this particular inclinable headrest, a pair of elongated holes are typically formed in the bottom side of headrest body and the two headrest stays extend outwardly through the respective such pair of elongated holes, thereby permitting the headrest body to be inclinable in the forward and backward directions relative to the two headrest stays.

As stated earlier, even in this inclinable headrest, the aforementioned injection hole is normally formed in a bottom surface of the trim cover assembly that covers the bottom side of headrest body, in order that a liquid foaming agent may be injected through the injection hole into the inside of the trim cover assembly during the foaming process.

As a result thereof, when the headrest is inclined forwardly relative to the headrest stays, the bottom side thereof shows up on a backward side of the seat, thus resulting in such injection hole being clearly viewed from the rear side of vehicle. This undesired problem also arises for backward inclination of the headrest; namely, with the headrest inclined backwardly relative to the headrest stays, the injection hole is then clearly viewed from the front side of vehicle. Such appearance of injection hole is objectionable and impairs the aesthetic appearance of headrest.

SUMMARY OF THE INVENTION

In view of the above-stated drawbacks, it is a purpose of the present invention to provide an improved inclinable headrest for automotive seat, which is devoid of the afore-said injection hole in the bottom side of the headrest, to thereby maintain aesthetic appearance of the headrest itself.

In order to achieve such purpose, in accordance with the present invention there is basically provided a headrest inclinable relative to at least one headrest stay, the headrest having at least one elongated hole formed in one side thereof and being formed by a foaming process involving the steps of: providing a three-dimensional trim cover assembly preformed in a predetermined shape conforming to a contour of the inclinable headrest, with the afore-said at least one headrest stay being placed in that particular three-dimensional trim cover assembly such that a part of the former projects outwardly from latter at a point for forming such at least one elongated hole; injecting a liquid foaming agent into the inside of the three-dimensional trim cover assembly, excepting the afore-said point for forming the at least one elongated hole, and then curing the liquid foaming agent into an increased mass of a foam padding filled in the three-dimensional trim cover assembly in integral manner, excepting the at least one elongated hole, the headrest comprising:

the three-dimensional trim cover assembly including a wall disposed on the one side of the headrest;

-   -   the foam padding filled in the three-dimensional trim cover         assembly;     -   the at least one elongated hole formed in the wall of the         three-dimensional trim cover assembly as well as in a local area         of the foam padding corresponding to the wall of the         three-dimensional trim cover assembly;     -   the at least one headrest stay extending outwardly through the         at least one elongated hole; and     -   an injected point at which the liquid foaming agent has been         injected into the three-dimensional trim cover assembly during         the foaming process, the injected point being provided within         the at least one elongated hole.

Another features and advantages of the present invention will become apparent from reading of the description, hereinafter, with reference to the annexed drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 a partly broken schematic perspective view showing an inclinable headrest of the present invention to be mounted on a seat back;

FIG. 2 is a partly broken schematic perspective view of a foaming die apparatus for forming the inclinable headrest;

FIG. 3 is a fragmentary sectional view of the foaming die apparatus and principal parts of the present invention, which shows a liquid foaming agent as being injected into the inside of trim cover assembly during a foaming process; and

FIG. 4 is a sectional view showing a resulting inclinable headrest of the present invention formed in the foaming die apparatus.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT OF THE INVENTION

FIG. 1 shows an inclinable headrest (HR) for use on automotive seat in accordance with the present invention. FIG. 2 shows a foaming die apparatus for forming such inclinable headrest (HR), and FIGS. 3 and 4 are illustrative of a foaming process using that foaming die apparatus to produce the inclinable headrest (HR).

The headrest (HR) is depicted in the FIG. 1 to have a pair of headrest stays (S) and (S1) which extend downwardly from the bottom side thereof and are fixedly mounted on the top of a seat back (SB) of an automotive seat. As shown, fromed in the bottom of the headrest (HR) are a pair of elongated holes (1) and (2) through which the two headrest stays (S) (S1) pass, respectively, into the inside of the headrest (HR).

As indicated by the dotted lines in FIG. 1, two headrest stays (S) (S1) are connected integrally with a horizontal axis element (S2) within the headrest (HR). While not clearly shown, the headrest (HR) itself is rotatably coupled with such horizontal axis element (S2) via some frame members.

Thus, it is to be seen that the provision of the two elongated holes (1) (1A) and horizontal axis element (S2) allows the headrest (HR) to be free to rotate or incline about that horizontal axis element (S2) in a direction to either of a forward side (F) and a backward side (B) of the seat back (SB) (or of an automotive seat), as indicated by the arrow in FIG. 1.

As understandable from FIGS. 1, 3 and 4, the body of the headrest (HR) is basically formed by a three-dimensional trim cover assembly (4) and a foam padding (3), as known in the art. The trim cover assembly (4) is performed by sewing together a plurality of cover materials into a predetermined three-dimensional shape conforming to a contour of the headrest (HR). As can be seen from FIGS. 1 and 3, the trim cover assembly (4) has a bottom surface (40) in which formed are a pair of generally cylindrical cover portions (40A) (40B) projecting inwardly of the trim cover assembly (4). Such two generally cylindrical cover portions (40A) (40B) are just defined in corresponded with the respective afore-said two elongated holes (1) (1A)

The foam padding (3) is filled in or has been created in the foregoing trim cover assembly (4) through a foaming process to be described later. While not clearly shown, it is to be understandable from FIGS. 1 and 4 that a bottom side of the foam padding (3), corresponding to the bottom side (at 40) of headrest (HR), has, formed therein, a pair of elongated bores (at 3H in FIG. 4) which are one of elements for constituting the foregoing elongated holes (1) (1A).

Hence, it is seen that the two cylindrical cover portions (40A) (40B) of trim cover assembly (4) cover the respective two inner surfaces of the afore-said two elongated bores (3H), thus constituting the pair of elongated holes (1) (1A) in the bottom side of the headrest (HR). (See FIG. 4 in conjunction with FIG. 1 for better understanding in that respect.)

As previously noted in the description of prior art, due to the forward and backward inclinability of headrest (HR), it is inevitable that the bottom side (at 40) of headrest (HR) has to be clearly viewed from either backward side (B) or forward side (F), and therefore, it is desirable that any injection hole for foaming process purpose should not be formed in that bottom side of headrest (HR), excepting the two elongated holes (1) (1A), in order to maintain aesthetic appearance of the headrest (HR) per se.

In accordance with the present invention, as apparently seen in FIG. 1, the inclinable headrest (HR) is devoid of any injection hole adapted for allowing an injection nozzle to insert there through into the inside of trim cover assembly (4) during a foaming process.

Now, a description will be made of a foaming process for forming such inclinable headrest (HR), which uses a novel construction of foaming die apparatus.

FIG. 2 shows a foaming die apparatus used in the present invention, which is comprised of: an upper die (UD) having a recessed die surface (UDa) defined therein, and a lower die (LD) having a recessed die surface (LDa) defined therein, the recessed die surface (LDa) being formed with a pair of protrudent die elements (D1) and (D2) integrally. Of course, such two protrudent die elements (D1) (D2) may be provided independently of and releasably attached to the lower die (LD). As understandable from FIGS. 2 and 3, the upper and lower dies (UD) (LD) may be mated with each other, so that a workable foaming space is defined between the respective two die surfaces (UDa) (LDa) thereof in a three-dimensional shape conforming to a predetermined three-dimensional contour of headrest body and thus confirming to the three-dimensional shape of trim cover assembly (4).

As illustrated, the two protrudent die elements (D1) (D2) may be integrally formed on a given vertical wall region (LDa-1) of the lower die (LD). Briefly stated, those two die elements (D1) (D2) are respectively adapted for forming the aforementioned two elongated bores (3B) in a resultant foam pad (3) together with the two cylindrical cover portions (40A) (40B) of trim cover assembly (4) to thereby form the two elongated holes (1) (1A) in a resultant headrest.

As best shown in FIG. 2 in conjunction with FIG. 3, a pair of headrest stay support through-holes (6) (6A) are formed in the foregoing two protrudent die elements (D1) (D2), respectively. Specifically, each of those two through-holes (6) (6A) extends through a corresponding one of the two protrudent die elements (D1) (D2) along the longitudinal axial direction thereof and further extends through the corresponding wall (at LDa-1) of the lower die (LD). Thus, the two through-holes (6) (6A) allows the two headrest stays (S) (S1) to pass therethrough and be supportively received therein, respectively, as will be set forth.

In accordance with the present invention, an injection through-hole (7) may be formed in one of the two protrudent die elements (D1) (D2) in a spaced-apart and parallel relation with one of the afore-said headrest stay support through-holes (6) (6A), as can best be seen from FIG. 3. As far as the illustrated embodiment is concerned, the injection through-hole (7) is formed in the left-side protrudent die element (D1). Precisely stated, the injection through-hole (7) extend through that left-side protrudent die element (D1) along the longitudinal axial direction thereof and further penetrates the corresponding wall (at LDa-1) of the lower die (LD), thus allowing insertion therethrough of the injection nozzle (N) to access the inside of the die, as will be set forth later.

In operation, at first, an incomplete headrest unit (HR′) is provided, which comprises the above-described trim cover assembly (4), the two headrest stays (S) (S1), the horizontal axis element (S2) and any other required element (not shown). As known in the art, in providing such incomplete headrest unit (HR′), those frame elements, i.e. the headrest stays (S and S1) and horizontal axis element (S2), including other required elements, are first inserted through the slit (2) formed in the bottom wall (40) of the trim cover assembly (4) and placed in the inside of that trim cover assembly (4), while passing only the two headrest stays (S) (S1) through the respective two through-holes (1) (1A) to the outside.

The thus-assembled incomplete headrest unit (HR′) is placed in a foaming space defined between the upper and lower dies (UD) (LD) as can be seen from FIG. 3. At this stage, the first step is to insert the two headrest stays (S) (S1) in the respective two headrest stay support through-holes (6) (6A) formed in the respective two protrudent die elements (D1) (D2), with the horizontal axis element (S2) being located inside of the lower die (LD). Of course, though not shown, any other required elements for forming the headrest (HR) may be located in the lower die (LD). Thereafter, the trim cover assembly (4) is placed in the lower die (LD), such that the two generally cylindrical cover portions (40A) (40B) thereof are in a close contact on and about the two protrudent die elements (D1) (D2), respectively, as can be seen in FIG. 3 in conjunction with FIGS. 1 and 2. Though not shown, as known in the art, any suitable sealing means may be provided to each of the two protrudent die elements (D1) (D2) to prevent outward leakage of liquid foaming agent (3A) through the cylindrical cover portions (40A) (40B), and also provided to the lower die wall region (LDa-1) on which the slit (2) of trim cover assembly (4) is contacted, in order to prevent outward leakage of the liquid foaming agent (3A) through that particular slit (2).

Then, after having engaged the upper die (UD) with the lower die (LD), an injection nozzle (N) is inserted through the injection through-hole (7) so that the distal end thereof projects in the inside of the engaged dies (UD and LD), followed by injecting a liquid foaming agent (3A) from the nozzle (N) into the inside of the trim cover assembly (4), as in FIG. 3. Upon completion of the foaming operation, as understandable from FIG. 4, the liquid foaming agent (3A) is cured into an increased mass of foam padding (3) which is filled in the trim cover assembly (4) together with the horizontal axis element (S2) as well as with the two headrest stays (S) (S1) in an integral manner.

Subsequent thereto, the upper die (UD) is removed from the lower die (LD) and then the resulting headrest (HR) is taken out from the lower die (LD). As understandable from FIG. 1, such resulting headrest (HR) has only the two elongated holes (1) (1A) in the bottom side thereof, with the two headrest stays (S) (S1) extending form those particular two elongated holes (1) (1A), respectively, without any injection hole present in that bottom side of headrest (HR).

As described above, in accordance with the present invention, it is appreciated that the following effects and advantages are attained:

(i) The liquid foaming agent (3A) is injected from the protrudent die element (D1 or D2) into the inside of trim cover assembly (40) at a point where the elongated hole (1 or 1A) is to be formed inside of resultant headrest (HR). Thus, any conventional injection hole for allowing injection of liquid foaming agent is not required in the bottom area (40) of trim cover assembly (4), and therefore, such absence of injection hole effectively keeps an aesthetic appearance of the headrest (HR) and also eliminates conventional troublesome requirement of sealing means to such injection hole to prevent leakage of liquid foaming agent therethrough.

(ii) Additionally, the liquid foaming agent (3A) is injected from a distal end of the protrudent die element (D1 or D2) far into the inside of trim cover assembly (4) at the point for formation of the elongated hole (1 or 1A). This means that the injected point (at P) where the liquid foaming agent (3A) has been injected into the trim core assembly (4) is substantially at an inner base (at 3D) of the elongated hole (1 or 1A) of resultant headrest (HR), or is located in the depth of that elongated hole. Thus, such injected point (P) is not viewed at all from the bottom side (at 40) of headrest (HR) which is to be shown up each time the headrest (HR) is inclined either forwardly or backwardly relative to the stays (S and S1). Further, even though the liquid foaming agent (3A) has been accidentally leaked from the injected point (P) and objectionably cured thereat during the foaming process, the disposition of that injected point (P) in the depth of elongated hole (1 or 1A) insures to completely conceal such objectionably leaked and cured state and make the same invisible from the outside. Accordingly, the present invention provides an aesthetically improved appearance of the inclinable headrest (HR)

Finally, is should be understood that the present invention is not limited to the illustrated embodiment, but any alternation, replacement and addition may be applied thereto without departing from the scopes of the appended claims. 

1-2. (canceled)
 3. A headrest inclinable relative to at least one headrest stay, wherein said headrest comprises: a three-dimensional trim cover assembly including a wall disposed on one side of said headrest; foam padding filled in said three-dimensional trim cover assembly; at least one elongated hole formed in said wall of said three-dimensional trim cover assembly and also formed in a local area of said foam padding corresponding to said wall of said three-dimensional trim cover assembly so as to be recessed inwardly of the headrest, with an inner base (3D) located at a depth of said at least one elongated hole; an injection hole formed on said inner base (3D) through which said foam padding was filled in said three-dimensional trim cover assembly; a first portion of said at least one headrest stay being rotatably connected with said headrest within said foam padding; a second portion of said at least one headrest stay extending from said inner base (3D) of said at least one elongated hole and also extending through said at least one elongated hole to an outside of said one side of the headrest; said at least one elongated hole permitting said second portion of said headrest to be movable therein relative to said first portion of said at least hole headrest stay, thereby allowing the headrest to be inclinable relative to said at least one headrest stay; and wherein a localized part of said foam padding, which corresponds to said injection point (P), is located at said inner base (3D) of said at least one elongated hole, while being distant from said second portion of said at least one headrest stay that extends from said inner base (3D).
 4. A headrest inclinable relative to at least one headrest stay, said headrest having at least one elongated hole formed in one side thereof, said at least one elongated hole having an inner base (3D) defined at a depth thereof, wherein said headrest is formed by a foaming process comprising the steps of: providing a three-dimensional trim cover assembly preformed in a predetermined shape conforming to a contour of said headrest, with said at least one rigid stay being placed in said three-dimensional trim cover assembly such that a first portion thereof is located within said three-dimensional trim cover assembly, while a second portion thereof projects outwardly from said three-dimensional trim cover assembly; providing a foaming die including a die portion adapted to form said at least one elongated hole, said die portion including a die surface for forming said inner base of said at least one elongated hole, a first through-hole (6), and a second through-hole (7), wherein said first and second through-holes open to said die surface in a spaced-apart relationship to each other and extend through said die portion; placing said three-dimensional trim cover assembly in said foaming die, so that said second portion of said at least one headrest stay extends through said first through-hole of said die portion; injecting a liquid foaming agent through said second through-hole into an inside of said three-dimensional trim cover assembly; whereupon an injection point (P) for said liquid foaming agent is established at said second through-hole (7); and curing said liquid foaming agent into an increased mass of foam padding which is filled in said three-dimensional trim cover assembly in integral manner, so that said at least one through-hole is formed by said die portion in said foam padding; wherein said headrest comprises: said three-dimensional trim cover assembly including a wall disposed on said one side of said headrest; said foam padding filled in said three-dimensional trim cover assembly; said at least one elongated hole formed in said wall of said three-dimensional trim cover assembly and also formed in a local area of said foam padding corresponding to said wall of said three-dimensional trim cover assembly so as to be recessed inwardly of the headrest, with said inner base (3D) located at a depth of said at least one elongated hole; said first portion of said at least one headrest stay being rotatably connected with said headrest within said foam padding; said second portion of said at least one headrest stay extending from said inner base (3D) of said at least one elongated hole and also extending through said at least one elongated hole to outside of said one side of the headrest; and said at least one elongated hole being of such configuration that allows said second portion of said the headrest to be movable therein relative to said first portion of said at least hole headrest stay, thereby allowing the headrest to be inclinable relative to said at least one headrest stay; wherein a localized part of said foam padding, which corresponds to said injection point (P), is located at said inner base (3D) of said at least one elongated hole, while being distant from said other portion of said at least one headrest stay that extends from said particular inner base (3D). 